Visible light isn't the only kind of radiation used in 3-D scanning. Computed tomography (CT) employs high-energy X-rays to penetrate the surfaces of objects, allowing researchers to construct multidimensional models of hidden structures. The technique was used to image the bones of our primate ancestor, Lucy, for clues to her distinctive physical traits and lifestyle.

The false-color 3-D rendering of her mandible was constructed from 801 cross-sectional slices, each 129 microns thick. A portion of the rendering was cut away to reveal the roots of her teeth.